diff --git a/backend/GNUmakefile b/backend/GNUmakefile
deleted file mode 100644
index 17d28d3..0000000
--- a/backend/GNUmakefile
+++ /dev/null
@@ -1,19 +0,0 @@
-
-CFLAGS = -std=c17 -Wall -Wextra -Wpedantic -Wconversion
-
-HEADERS = $(wildcard *.h)
-
-all: compile_flags.txt server
-
-server: main.o linux.o
-	gcc $^ -o $@
-
-%.o: %.c $(HEADERS)
-	gcc $< -c -o $@ $(CFLAGS)
-
-clean:
-	rm -rf *.o server client
-
-compile_flags.txt:
-	echo -xc $(CFLAGS) | sed 's/\s\+/\n/g' > compile_flags.txt
-
diff --git a/backend/Makefile b/backend/Makefile
index 5a26094..ebfdd98 100644
--- a/backend/Makefile
+++ b/backend/Makefile
@@ -1,12 +1,19 @@
 
-OBJS=main.obj windows.obj
+CFLAGS = -std=c17 -Wall -Wextra -Wpedantic -Wconversion
 
-all: $(OBJS)
-    link /out:server.exe $(OBJS) WS2_32.lib
+HEADERS = $(wildcard *.h)
 
-.obj:
-    cl $*.c
+all: compile_flags.txt server
+
+server: main.o linux.o http.o
+    gcc $^ -o $@
+
+%.o: %.c $(HEADERS)
+    gcc $< -c -o $@ $(CFLAGS)
 
 clean:
-    del *.obj server.exe
+    rm -rf *.o server client
+
+compile_flags.txt:
+    echo -xc $(CFLAGS) | sed 's/\s\+/\n/g' > compile_flags.txt
 
diff --git a/backend/NMakefile b/backend/NMakefile
new file mode 100644
index 0000000..5a26094
--- /dev/null
+++ b/backend/NMakefile
@@ -0,0 +1,12 @@
+
+OBJS=main.obj windows.obj
+
+all: $(OBJS)
+    link /out:server.exe $(OBJS) WS2_32.lib
+
+.obj:
+    cl $*.c
+
+clean:
+    del *.obj server.exe
+
diff --git a/backend/http.c b/backend/http.c
new file mode 100644
index 0000000..5ad2e5b
--- /dev/null
+++ b/backend/http.c
@@ -0,0 +1,26 @@
+#include "http.h"
+#include <stdlib.h>
+
+HttpRequestHeader parse_http_request_header(const char* message, size_t message_size)
+{
+    size_t i = 0;
+
+    // parse method
+    HttpMethod method;
+    if (i + 3 < message_size && strncmp(&message[0], "GET", 3)) {
+        method = HttpMethodGet;
+        i += 3;
+    } else if (i + 4 < message_size && strncmp(&message[0], "POST", 4)) {
+        method = HttpMethodPost;
+        i += 4;
+    } else {
+        printf("error: header parse fail #1\n");
+        exit(1);
+    }
+
+    // skip space
+    i += 1;
+    if (i >= message_size) { }
+
+    return (HttpRequestHeader) { 0 };
+}
diff --git a/backend/http.h b/backend/http.h
new file mode 100644
index 0000000..b4e8e35
--- /dev/null
+++ b/backend/http.h
@@ -0,0 +1,19 @@
+#ifndef HTTP_H
+#define HTTP_H
+
+#include <stdlib.h>
+
+typedef enum {
+    HttpMethodGet,
+    HttpMethodPost,
+} HttpMethod;
+
+typedef struct {
+    HttpMethod method;
+    size_t path_index, path_length;
+    size_t content_length;
+} HttpRequestHeader;
+
+HttpRequestHeader parse_http_request_header(const char* message, size_t message_size);
+
+#endif
diff --git a/backend/main.c b/backend/main.c
index b908f69..59db0f7 100644
--- a/backend/main.c
+++ b/backend/main.c
@@ -1,46 +1,10 @@
+#include "native.h"
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
-#include "native.h"
-
-typedef enum {
-    HttpMethodGet,
-    HttpMethodPost,
-} HttpMethod;
-
-typedef struct {
-    HttpMethod method;
-    size_t path_index, path_length;
-    size_t content_length;
-} HttpRequestHeader;
-
-HttpRequestHeader parse_http_request_header(const char* message, size_t message_size)
-{
-    size_t i = 0;
-
-    // parse method
-    HttpMethod method;
-    if (i + 3 < message_size && strncmp(&message[0], "GET", 3)) {
-        method = HttpMethodGet;
-        i += 3;
-    } else if (i + 4 < message_size && strncmp(&message[0], "POST", 4)) {
-        method = HttpMethodPost;
-        i += 4;
-    } else {
-        printf("error: header parse fail #1\n");
-        exit(1);
-    }
-
-    // skip space
-    i += 1;
-    if (i >= message_size) { }
-
-    return (HttpRequestHeader) { 0 };
-}
-
 const uint16_t port = 8000;
 
 int main(void)